Measurement of glycoprotein content and cell kinetics in preulcerous gastric mucosa

In an attempt to evaluate the role of gastric mucosal defense factors in ulcerogenesis, we measured the levels of glycoproteins in the mucosa as well as mucosal cell turnover in the preulcerous phase and compared these parameters to the normal mucosa in the same animal. Ovalbumin-presensitized Praomys (Mastomys) natalensis were challenged in the gastric wall with ovalbumin and a gastric ulcer developed at the challenge site 3 days later as a result of a mucosal anaphylactic reaction. This model enabled us to study the events occurring at the site of a future ulceration. Gas-liquid chromatographic determination of mucosal glycoproteins showed that the normal and preulcerous mucosae had similar levels. Cell turnover, determined by [3H]thymidine incorporation, was stimulated as a result of the preulcerous anaphylactic reaction at 24 hours postchallenge whereas at 48 hours the values were not different from those obtained in controls. These results suggest that the pathogenesis of anaphylactic gastric ulcer involves a change in cell turnover but no changes in the production of gastric mucus.